The present invention relates generally to amplifiers, and more specifically the invention pertains to laser diodes. The invention also relates to high power laser diodes of the type known as master oscillator power amplifier (MOPA) devices, and especially to MOPAs with flared amplifiers.
Conventional "hard-edged" amplifiers produce top-hat near fields with appreciable structure due to edge effects. These systems have experienced relatively poor beam quality due to edge effects of the "hard-edged" flared amplifiers which contribute to the near fields of their laser diode components. The task of feathering out the near field effects to improve beam quality is alleviated, to some extent, by the systems described in the following U.S. patents, the disclosures of which are incorporated herein by reference:
U.S. Pat. No. 5,321,718 issued to Waarts et al; PA1 U.S. Pat. No. 4,965,525 issued to Zah; and PA1 U.S. Pat. No. 5,337,328 issued to Lang.
The above-cited patents disclose semiconductor laser designs that are improved by the present invention.